Hemming attachment for sewing machines



May 5, 1942- J. P; ENOS HEMMING ATTACHMENT FOR SEWING MACHINES Filed Nov. 19, 1940 Cbhn 1? [nos Wifmm Patented May 5, 1942 UNiTE ST 1T E S PATENT OFFICE HEMMING ATTACHMENT FOR SEWING MACHINES Application November 19, 1940, Serial No. 366,199

Claims.

This invention relates to useful improvements in sewing machine hemming attachments generally, although more particularly to a hemmer of the scroll and arbor type for forming an extremely narrow hem.

In using attachments of this type considerable difficulty is occasioned at times in hemming fabrics having cross-seams therein, In traversing such cross-seams the hemmer frequently becomes choked or clogged, inasmuch as the desirably small capacity of the attachment is exceeded by the relatively thick cross-seam. In view of this clogging, it has become common practice to provide hemmers with resiliently supported sections adapted to yield under the influence of variations in the thickness of the fabric being hemmed. These sections, in the majority of cases, are adapted to yield in a direction normal to the line of seam-formation and in order for these sections to so move considerable pressure must be applied thereto by the cross-seam which has the eifect of impeding the progress of the fabric through the hemmer. The sewing machine feed-dog operates to overcome the impedance of the fabric, but in so doing effects a distortion of the fabric margin comprising the hem-fold, resulting in imperfections in the finished seam.

It is the primary object of the present invention to provide a hemmer having a scroll and arbor, wherein the scroll is yieldingly supported for movement in an arcuate path away from the arbor and in a direction inclined rearwardly and away from the normal line of seamformation.

A further object of the present invention is the provision of a simple and effective means for yieldingly supporting the scroll member of a hemming attachment, whereby the capacity of the attachment can be automatically varied to accommodate fabrics having thickened portions therein, such as cross-seams or the like.

The invention further relates to arrangements and combinations of parts which will be more fully described hereinafter, pointed out in the appended claims and illustrated in the accompanying drawing, in which- Fig. 1 is a perspective view of a hemmer foot embodying the invention and shown as applied to a sewing machine.

Fig. 2 is a top plan view of the improved hemmer.

Fig. 3 is a bottom plan view of the hemmer.

Fig. 4 is a right side elevational view of the hemmer.

with the sole-plate I.

Fig. 5 is a top plan View of the hemmer-scroll and its pivotal carrier-arm.

Referring more in detail to the drawing the preferred embodiment of the invention comprises a presser-foot hemmer including a basemember or sole-plate I having a shank 2 secured by a thumb-screw 3 upon the lower end of the usual presser-bar 4 of a sewing machine having a throat-plate 5 and a reciprocatory needle-bar 6 carrying the needle I. The sole-plate I at its forward end is bifurcated to provide spaced toes 8 and 9, and is apertured, as at In, to provide the usual needle-hole.

Soldered or otherwise suitably secured to the toe 8 is the shank H of an arbor l2, the free end of which is directed toward the needle-hole Ill. The arbor I2 is preferably conical in shape in order that it will be sufficiently large in crosssection at any one point within its work-controlling length as to fill the tubular fold of fabric formed by the hemmer. By thus filling the tubular fold the same is prevented from collapsing prematurely, with the result that the tendency of the raw edge of the fabric to uncurl is reduced to a minimum.

Cooperating with the conical arbor I2 is the usual hemmer scroll l3 having a leading edge 14 which extends spirally rearwardly between the toes 8 and 9 toward the needle-hole H1. The scroll I3 is initially arranged in close proximity to the conical arbor l2 to effectively control thin fabrics. When so constructed, the hemmer will expeditiously handle thin fabrics, but at the same time it is susceptible of choking in the event a cross-seam or the like enters the hemmer. To eliminate this choking the hemmer scroll I3 is supported so that it may yield bodily in an arcuate path away from the arbor l2 in a direction inclined rearwardly with respect to the direction of the normal feed of the work through the hemmer. To this end, the scroll I3 is soldered or otherwise secured to the forward end of a pivotal carrier-arm l5 fulcrumed intermediate its ends upon a vertical pivot-stud l6 threaded into a lateral extension I1 integral At its rearward 'end the carrier-arm I5 is enlarged and formed with an elongated slot I8 entered by a stop-screw I9 also threaded into the lateral extension H. The ends of the elongated slot l8 cooperate with the shank of the stop-screw l9 to limit the swinging movement of the scroll l3. The scroll I3 is maintained in its normal operative relation with the arbor I2 by a spring-wire 28 coiled about the pivot-stud IE and having one of its ends anchored in an aperture 2| in the carrier-arm I5 and its other end anchored in an aperture 22 provided in the lateral extension ll.

It will be understood that as a cross-seam in the fabric, indicated as S in Fig. 1, is drawn into the hemmer, the thickened portion of the fabric engages the spiralled edge Id of the hemmer scroll I3 and acts to shift the scroll. away from the arbor l2 in an are about the axis of the pivot-stud 16, thereby to increase the capacity of the hemmer. After the cross-seam .8 passes beyond the hemmer, the scroll I3 returns to its normal operating position under the action of the spring-wire 20.

It will be observed in Fig. 2-that the pivotstud I6 is disposed to the right of the needlehole Ill and between the needle-hole and thereceiving end, or mouth, of the hemmer. When located in this position, the initial arcuate movement of the scroll l3 about the axis of the pivotstud I6 is in a direction inclined rearwardly and away from the line of seam-formation.

When the scroll l3 movesin this direction, there is a component of movement normal to the line of feed and a component of movement parallel to the line of feed. The effort required to shift the scroll circularly in a rearwardly inclined direction is materially less than thatrequired to shift the scroll in a direction normal to the line of feed, as is the usual direction of the movement .of the scroll in prior attachments of this type. The resultant reduction in the .efiort required to shift the scroll lessens to a'large extent the resistance to the passage of the fabric through the hemmer, with the consequence that the distortion of .the marginal portion of the fabric adjacent the cross-seam is minimized.

From the foregoing description, it is obvious thatvthe present invention contemplates an improved hemmer attachment having a variable capacity automatically regulated by the thickness of the 'fabric being hemmed,the scroll of the hemmer being supported in such a way as to ofier a minimum of resistance to the passage of the fabric through the hemmer.

Having thus set forth the nature of the invention what I claim herein is:

l. A sewing machine hemming attachment comprising a base-member, an arbor fixed to said'base-member and disposed so that its free end extends substantially in the normal direction of feed, a work folding scrollcomplemental to said arbor, a carrier-arm sustained upon said base-member and supporting said work-folding scroll for movement relative to said arbor in a direction inclined rearwardly and away from the normal line of seam formation, means for limiting the movement of said carrier-arm, and means for biasing-said work-folding scroll. into cooperative position with said arbor. I

2. A sewing machine hemming attachment comprising a base member, an arbor'fixed to said base-member and disposed so that its free end extends substantially in the normal direction of feed, a work-folding scroll complemental to said arbor, a carrier arm fulcrumed upon said member, an arbor fixed to said base-member and disposed so that its free end extends substantially in the normal direction of feed, a work- 'fclding scroll complemental to said arbor, a carrier-arm-fulcrumed upon said base-member and supporting said work-folding scroll, a pivot-stud projecting through said carrier-arm and threaded into said base-member in position so that the work-folding scroll in its movement relative to said arbor shifts in a direction inclined rearwardly and away from the normal line of seamformation, means for limiting the movement of said scroll, and a spring-wire for biasing said work-folding scroll into cooperative relation with said arbor, said spring-wire being coiled about said pivot-stud and having one of its ends anchored in said carrier-arm and the other of its ends anchored in said base-member.

4. A hemming attachment comprising a basemember, an arbor fixed to said base-member and disposed so that its free end extends substantially in the normal direction of feed, a workfolding scroll complemental to said arbor, a carrier-arm fulcrumed upon said case-memberand supporting'said work-folding scroll and having formed therein an elongated aperture, apivotstud projecting through said carrier-arm and threaded into said base-member in position so that the work-folding scroll in its movement relative to said arbor shifts in a direction inclined rearwardly with respect to the normaldirection o'ffeed of the work through the attachment,-means forlimiting the movement of said scroll including a stop-screw projecting through said elongated aperture in said carrier arm and threaded into said base-member, and a spring for biasing said work-folding scroll into cooperative relation with said arbor.

5. A presser-ioot hemmerhaving a sole-plate provided with a needle-hole and at its forward end with spaced toes, an arbor carried by one of said toes, a work-folding scroll complemental to said arbor and having a spiralled leading edge extendingrearwardly in the space between'said toes, a' lateral extension provided on said soleplate adjacent the other of said toes,- a carrierarm fulcrumed upon a pivot-stud threaded into said extension and formed at one end with an elongated aperture and supporting at its other end said work-folding scroll, a stop on said lateral extension projecting through said elongated aperture and cooperating with the opposite ends thereof to limit the pivotal movement of said carrier-arm, and a spring for maintaining said work-folding scroll in cooperative relation with saidarbor.

JOHNP. ENOS. 

